# std::chrono::operator==,<=>(std::chrono::year_month_day_last)

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< cpp‎ | chrono‎ | year month day last

Defined in header `<chrono>` |  |
constexpr bool operator==( const std::chrono::year_month_day_last& x, const std::chrono::year_month_day_last& y ) noexcept; | (1) | (since C++20)
constexpr std::strong_ordering operator<=>( const std::chrono::year_month_day_last& x, const std::chrono::year_month_day_last& y ) noexcept; | (2) | (since C++20)

Compares the two `year_month_day_last` values x and y. This is a lexicographical comparison: the `year()` is compared first, then `month()`.

The `<`, `<=`, `>`, `>=`, and `!=` operators are synthesized from operator<=> and operator== respectively.

### Return value

1) x.year() == y.year() && x.month() == y.month()
2) x.year() <=> y.year() != 0 ? x.year() <=> y.year() : x.month() <=> y.month()

### Notes

If both x and y represent valid dates (x.ok() && y.ok() == true), the result of the lexicographical comparison is consistent with the calendar order.

### Example

Run this code

    #include <cassert>
    #include <chrono>
    #include <iostream>

    int main()
    {
        auto ymdl1{11/std::chrono::last/2020};
        auto mdl{std::chrono::last/std::chrono::November};
        auto ymdl2{mdl/2020};
        assert(ymdl1 == ymdl2);

        ymdl1 -= std::chrono::months{2};
        ymdl2 -= std::chrono::months{1};
        assert(ymdl1 < ymdl2);
    }

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